This patch defines necessary variables for the 'hashi_vault' pki backend which is the alternative to the default 'standalone' backend. Additionally, it: - changes the format of `placement_pki_san` to the new one changed in [1] - passes `pki_default_backend` when trigerring PKI role so its aware of the default backend in case it's not explicitly specified in the cert definition. - adopts this role to the recent changes in PKI role [2][3][4] [1] https://review.opendev.org/c/openstack/openstack-ansible/+/948886 [2]fc7db02074[3]7cff89ee71[4]f03bcc19d5Change-Id: I556c40bbc4bf683b660b131ba3d302a4dde5e437 Signed-off-by: Damian Dabrowski <damian.dabrowski@cleura.com>